Library API

A RESTful Web API built with C# and ASP.NET Core for managing a library of books.

This project was developed to practice ASP.NET Core Web API, layered architecture, dependency injection, DTOs, business rules, validation, exception handling, and RESTful API development.

Technologies

• C#
• .NET
• ASP.NET Core Web API
• Swagger / OpenAPI
• Visual Studio

Features

• List all books
• Get a book by ID
• Create a book
• Update a book
• Delete a book
• Input validation
• Business rule validation
• Genre validation and conversion
• Duplicate book validation
• CreatedAt and UpdatedAt timestamps
• HTTP status code handling

Business Rules

• Book title and author combination cannot be duplicated.
• Price cannot be negative.
• Stock cannot be negative.
• Genre must be valid.
• CreatedAt is set when a book is created.
• UpdatedAt is updated when a book is modified.

Architecture

Controller

Responsible for handling HTTP requests and responses, route parameters, and HTTP status codes.

Service

Responsible for business rules such as price, stock, genre, and duplicate book validation.

DTOs

Used to separate API request/response models from the internal Book model.

API Endpoints

Method	Endpoint	Description
GET	/api/books	Get all books
GET	/api/books/{id}	Get a book by ID
POST	/api/books	Create a book
PUT	/api/books/{id}	Update a book
DELETE	/api/books/{id}	Delete a book

What I Practiced

Through this project, I practiced:

• ASP.NET Core Web API fundamentals
• RESTful API design
• HTTP methods and status codes
• Dependency Injection
• Layered Organization (Folders)
• DTOs
• Business rule implementation
• Input validation
• Exception handling
• LINQ
• Debugging with Visual Studio

How to Run

Prerequisites

Make sure you have installed:

• .NET SDK
• Visual Studio 2022 or another C#/.NET IDE

1. Clone the repository

git clone https://github.com/AnaLinsDev/library-api.git

2. Navigate to the project

cd LibraryAPI

3. Restore dependencies

dotnet restore

4. Build the project

dotnet build

5. Run the API

dotnet run

The terminal will display the URL where the API is running.

6. Open Swagger

Open the Swagger URL displayed by the application in your browser.

Swagger can be used to test the available API endpoints without requiring Postman or another API client.